Manually removing program from registry

[Seizure Explosion]

A quickie, hopefully-

I had a program that wouldn't uninstall properly, so I went into program files and deleted all its resources to clear up some desperately needed HDD space. However, now a new version of that program has come out and it wants to try and uninstall the previous version, but there's nothing there to uninstall, which leaves me in a bit of a pickle. What I need to do now is make Windows figure out that there's no longer a program there. Do I need to reinstall the old version and try uninstalling the old fashioned way or can I go into windows and force the notion that the program is no longer with us on the OS manually?

[heatlesssun]

This can get ugly quick unless you know what to look for. Did the new version of the program not install? Even if the program files are gone, the installer might still work.

There are a lot of good free registry cleaning tools that might help if that doesn't work.

[digital_exhaust]

CCleaner works pretty well, as does RegScrubXP.

But I would be a bit surprised if either will solve the problem. And as mentioned above, be careful digging around in your registry unless you know exactly what your looking for....

[Kowan]

There are a lot of good free registry cleaning tools that might help if that doesn't work.
CCleaner (http://www.ccleaner.com/) is a great one.